Post by dave FF 50-aka "Harm" on Sept 29, 2011 16:58:00 GMT -8
HOOSIER R60A INFORMATION UPDATE.
I had productive telephone conversations with both Bruce Foss (Senior Product Manager at Hoosier Racing Tires back in Indiana) and Tim Gerhardt (Hoosier Tire West) a few days ago about the R60a tires which I have nutshelled here. I have asked Bruce to look over this summation to confirm accuracy but he has not been able to get back to me before I needed to send this out so you may be getting a correction email next week.
HISTORY:
The R60 was originally made for the Central Division Club Ford drivers about 12 years ago and was called the R60CD. It was found to be popular, was marketed across the country and well accepted with other Club Ford groups. About 4 years ago the tire became the R60a with a mold and compound change.
WORKING TIRE PRESSURES AND TEMPS:
Bruce recommended hot pressures of 18/19, a bit more than some of us were thinking appropriate. Experiments by Michael Bernstein and Dave Jalen support these higher pressures, and even higher. Not sure why we are getting this recommendation now and not two years ago.
Working temps are 135° on the low side to 260° on the high side, so we have no worry about overheating the tire but on cold days we do need to pay attention to getting temperature into the tire .
TIRE CARCASS NOT CENTERED ON THE RIM CONCERNS:
Some concerns have been heard about the tire tread/carcass not being centered on the rim. Bruce said it is just unavoidable with a bias ply/cantilever sidewall tire and is one of the reasons they make the high end tires with Kevlar. He suggested for those that have interference issues with uprights (some DB-1's and DB-6's) the first step is to flip the tire on the rim to take advantage of the offset if there is any.
CONCERNS ABOUT TIRE TEMPS BEING HIGHER IN CENTER:
Bruce recommended the ideal tire temp range across the tread after a track session should have the inside edge about 20° hotter than the outside edge. One would hope the middle surface to be about 10° between the two but some of us have found no matter what pressures we run the center runs a bit hotter than the average of the outside/inside. Bruce said they found the same thing but felt it was the best compromise when combined with tire life and performance. So don't do like I did and lower the cold pressures to 10/12 at the start of the race in an effort to get the center temps down as the car will be basically undriveable for several laps. Think old American Racers. As an aside some of you might remember this is the opposite to a problem we had with Goodyear 430's a while back which commonly had a dip in the center of the tread.
HOOSIER RAIN TIRES:
Hoosier FF rain tires are built on a non-Kevlar carcass. On a personal note the Hoosier rains (labeled "Wet") I bought 11 years ago are still working fine, with little side wall cracking. Not inexpensive, but an excellent product.
WHAT IS A HEAT CYCLE:
Regarding what constitutes a heat cycle, both Bruce and Roger Kraus stated while having tires just sitting in the heat of the sun (which can result in tire temps well over 120°) is not good (it causes the oils to cook out, which is where the bluish sheen appearance comes from) it does not constitute a heat cycle, at least in the short term. Physical movement of the tire during use on the track and centrifugal force are required to create the conditions for a heat cycle as we think of it. That being said leaving the tires unwrapped (Bruce recommends a tight black garbage bag for storage) in the sun all summer will probably cook them to the effect of many heat cycles. So time and physical action is a factor in the decay of the tires grip.
Bottom line is a 'heat cycle' as we think of it is really a track generated phenomenon, though heat alone can have the same degradation affect in the long term.
NEW GOVERNMENT REGULATIONS:
In four years government regulation is requiring non-aromatic oils in the compounds. Hoosier is currently changing over the construction of some of their line and the R60a will follow suit at some point in the future. They will tell us when this happens. Bruce does not expect this to affect the performance of the tire but it is too soon to understand fully what the effect will be or the effect on cost.
2012 TIRE INVENTORY CONTROL, PRICING AND CONTINGENCY PROGRAM:
Bruce suggested we let Tim Gerhardt (Hoosier Tire West, the local distributor) know approximately how many tires we will need next year and when. I think we can guess how many participants we will have and we can give him a schedule for the events. I will take care of that.
Bruce gave me estimated prices for the R60a's in 2012 as $144.10 for the fronts, 173.80 for the rears, $635.80 a set. Not the bargain they were last year at $550 a set but still a very good deal compared to Goodyear's and Hoosier's pricing for their top-line FF tires (over $800 in each case). For comparison the current pricing of R60a's is $131 for the fronts and $158 for the rears, $578 a set.
Tim Gerhardt told me the Hoosier Tire West administered contingency program will be continued for next season.
I had productive telephone conversations with both Bruce Foss (Senior Product Manager at Hoosier Racing Tires back in Indiana) and Tim Gerhardt (Hoosier Tire West) a few days ago about the R60a tires which I have nutshelled here. I have asked Bruce to look over this summation to confirm accuracy but he has not been able to get back to me before I needed to send this out so you may be getting a correction email next week.
HISTORY:
The R60 was originally made for the Central Division Club Ford drivers about 12 years ago and was called the R60CD. It was found to be popular, was marketed across the country and well accepted with other Club Ford groups. About 4 years ago the tire became the R60a with a mold and compound change.
WORKING TIRE PRESSURES AND TEMPS:
Bruce recommended hot pressures of 18/19, a bit more than some of us were thinking appropriate. Experiments by Michael Bernstein and Dave Jalen support these higher pressures, and even higher. Not sure why we are getting this recommendation now and not two years ago.
Working temps are 135° on the low side to 260° on the high side, so we have no worry about overheating the tire but on cold days we do need to pay attention to getting temperature into the tire .
TIRE CARCASS NOT CENTERED ON THE RIM CONCERNS:
Some concerns have been heard about the tire tread/carcass not being centered on the rim. Bruce said it is just unavoidable with a bias ply/cantilever sidewall tire and is one of the reasons they make the high end tires with Kevlar. He suggested for those that have interference issues with uprights (some DB-1's and DB-6's) the first step is to flip the tire on the rim to take advantage of the offset if there is any.
CONCERNS ABOUT TIRE TEMPS BEING HIGHER IN CENTER:
Bruce recommended the ideal tire temp range across the tread after a track session should have the inside edge about 20° hotter than the outside edge. One would hope the middle surface to be about 10° between the two but some of us have found no matter what pressures we run the center runs a bit hotter than the average of the outside/inside. Bruce said they found the same thing but felt it was the best compromise when combined with tire life and performance. So don't do like I did and lower the cold pressures to 10/12 at the start of the race in an effort to get the center temps down as the car will be basically undriveable for several laps. Think old American Racers. As an aside some of you might remember this is the opposite to a problem we had with Goodyear 430's a while back which commonly had a dip in the center of the tread.
HOOSIER RAIN TIRES:
Hoosier FF rain tires are built on a non-Kevlar carcass. On a personal note the Hoosier rains (labeled "Wet") I bought 11 years ago are still working fine, with little side wall cracking. Not inexpensive, but an excellent product.
WHAT IS A HEAT CYCLE:
Regarding what constitutes a heat cycle, both Bruce and Roger Kraus stated while having tires just sitting in the heat of the sun (which can result in tire temps well over 120°) is not good (it causes the oils to cook out, which is where the bluish sheen appearance comes from) it does not constitute a heat cycle, at least in the short term. Physical movement of the tire during use on the track and centrifugal force are required to create the conditions for a heat cycle as we think of it. That being said leaving the tires unwrapped (Bruce recommends a tight black garbage bag for storage) in the sun all summer will probably cook them to the effect of many heat cycles. So time and physical action is a factor in the decay of the tires grip.
Bottom line is a 'heat cycle' as we think of it is really a track generated phenomenon, though heat alone can have the same degradation affect in the long term.
NEW GOVERNMENT REGULATIONS:
In four years government regulation is requiring non-aromatic oils in the compounds. Hoosier is currently changing over the construction of some of their line and the R60a will follow suit at some point in the future. They will tell us when this happens. Bruce does not expect this to affect the performance of the tire but it is too soon to understand fully what the effect will be or the effect on cost.
2012 TIRE INVENTORY CONTROL, PRICING AND CONTINGENCY PROGRAM:
Bruce suggested we let Tim Gerhardt (Hoosier Tire West, the local distributor) know approximately how many tires we will need next year and when. I think we can guess how many participants we will have and we can give him a schedule for the events. I will take care of that.
Bruce gave me estimated prices for the R60a's in 2012 as $144.10 for the fronts, 173.80 for the rears, $635.80 a set. Not the bargain they were last year at $550 a set but still a very good deal compared to Goodyear's and Hoosier's pricing for their top-line FF tires (over $800 in each case). For comparison the current pricing of R60a's is $131 for the fronts and $158 for the rears, $578 a set.
Tim Gerhardt told me the Hoosier Tire West administered contingency program will be continued for next season.
